Reducing ironing effort using curved soleplate

ABSTRACT

A soleplate includes an operable portion of an ironing surface having a front edge located opposite a rear edge, and having a first side located opposite a second side. The soleplate includes a longitudinal axis bisecting the front edge and the rear edge. The soleplate also includes a transverse axis bisecting the first side and the second side based on a midpoint of the longitudinal axis. The soleplate also includes an intersection located where the longitudinal axis and the transverse axis cross. The operable portion of the ironing surface is substantially curved along the longitudinal axis and substantially curved along the transverse axis, forming a raised pinnacle of the operable portion located along the longitudinal axis at a point other than the intersection, the raised pinnacle forming a highest point on the operable portion.

BACKGROUND

Aspects of this disclosure are directed to irons, and in particular to reducing the effort required to operate irons.

Wrinkles in fabric are widely considered to be undesirable, but inevitable. Ironing has long existed as a way to reduce or remove wrinkles or creases in fabric. In earlier times, irons (also called flatirons, sadirons, or box irons, among others) were very simple devices, having a soleplate being a flat piece of metal that was contacted to an external heating element, removed from the heating element, and applied to the fabric, such as clothes or linens. The iron was then applied in a back-and-forth motion over the surface of the fabric until the iron cooled down due to ambient temperature, at which point the soleplate of the iron could be reheated or exchanged for another heated iron. Other types of irons employed hollow metal boxes containing various heating material, such as charcoal, in order to stay sufficiently hot. Early irons were very heavy due to the large amount of metal and/or heat source. Ironing with early irons generally took many passes and could be tiring and inefficient, especially over extended periods of time.

Later, self-heating electric irons were introduced, and could be used nearly continuously without stopping to reheat, refuel, or swap out the iron. The use of plastics and other lightweight materials in irons also increased, leading to reduced iron weight. Electric irons generally were heated using a resistive element located within a metal soleplate, which was usually made of aluminum or stainless steel. The metal soleplate could then be polished or coated in low-friction material to reduce manual effort while using the iron.

Incremental improvements over the years, such as the introduction of steam injection components, led to a more effective iron. A typical modern iron includes a reservoir and capacity to heat liquid water into steam and introduce the produced steam to fabric through holes located in the soleplate, causing fabric molecule bonds to loosen and to stretch under the weight, heat, and/or motion of the iron, leading to flatter, more uniformly pressed fabric. The fabric would then cool and typically stay pressed for a period of time. A typical iron typically heats a soleplate to roughly 180-220° Celsius (about 350-430° Fahrenheit), but may be hotter or cooler depending on the fabric to be ironed and the type and configuration of iron being used.

Typically, an iron assembly is composed of various components, including a main body housing, an electrical cord and wall plug, a soleplate, a handle, a stand to keep a hot soleplate off fabric when not in use, a reservoir, a steam injection system, and a thermostat, among other features. Wireless electric irons are becoming more common, and such wireless irons may contain an internal source of electrical energy, such as a battery. For both wired and wireless irons, the soleplate is typically the only useful aspect of an iron that intentionally contacts any fabric being ironed, and thus the soleplate is an important component of an iron.

The geometry of an iron soleplate is typically configured in a flat, roughly triangular lobed shape, and often has multiple holes formed in it for the passage of steam from a heated reservoir to the fabric being ironed. Generally, iron soleplates have a top and bottom surface that are substantially planar, with respect to the ironing surface of the soleplate that contacts the fabric, providing a nearly uniform pressure on all contact points of the soleplate to the fabric.

During ironing, it is typical to place fabric to be ironed on a flat, padded substrate (board) having an internal rigid structure. These substrates are commonly referred to as ironing boards. Ironing boards generally are configured to flex or give when pressure is applied to the board or fabric over the board, which may allow for flexibility and smoother ironing. An iron may interface with a board, causing the board to flex where the iron is located and applying pressure to the board, compressing the board. An ironing board may also have a heat-resistant and/or flame-retardant fabric covering over heat-resistant padding configured to reduce potential charring during ironing at elevated soleplate temperatures.

Today, despite many advancements in ironing technology, ironing is generally still considered to be a menial, undesired task. One particular facet of ironing that can bother some iron users is the tendency for an iron to “stick” when first being moved over fabric, which often happens numerous times during the back-and-forth motion of ironing. Once the iron is in motion it builds momentum and tends to keep sliding with relatively little effort (under kinetic/dynamic friction) but the initial take up point can be imprecise and tiring to a user's arm, leading to fatigue. Therefore, improvements to the ease of use of irons is desirable.

SUMMARY

This disclosure describes methods and structures related to soleplates for ironing devices that utilize a shaped soleplate surface to make initially moving an iron easier. Static friction is reduced at least in part due to a tilting motion of the iron upon initial force applied to the iron.

An improved soleplate can be configured to be shaped in such a way that the initial (i.e., static) friction that is involved in putting an object in motion is reduced, providing noticeably smoother glide action at the repeated onset of motion in an iron.

In various aspects, disclosed methods of making a soleplate, and structures related to a soleplate for use with an iron.

In a first and second aspect, a soleplate or ironing device includes an operable portion of an ironing surface having a front edge located opposite a rear edge, and having a first side located opposite a second side. The soleplate includes a longitudinal axis bisecting the front edge and the rear edge. The soleplate also includes a transverse axis bisecting the first side and the second side based on a midpoint of the longitudinal axis. The soleplate also includes an intersection located where the longitudinal axis and the transverse axis cross. Also according to the first and second aspect, the operable portion of the ironing surface is substantially curved along the longitudinal axis and substantially curved along the transverse axis, forming a raised pinnacle of the operable portion located along the longitudinal axis at a point other than the intersection, the raised pinnacle forming a highest point on the operable portion.

According to a variation of the first aspect, the operable portion of the ironing surface is substantially longer along the longitudinal axis than the transverse axis. According to another variation, the operable portion of the ironing surface is curved to reduce static friction during ironing. According to another variation, the substantially curved operable portion of the ironing surface along the longitudinal axis is parabolically curved such that the intersection is higher than the average of the front edge and rear edge. According to another variation, the substantially curved ironing surface along the transverse axis is parabolically curved such that the intersection is higher than the average of the first side and the second side. According to another variation, the operable portion of the ironing surface is configured to interface with an ironing board substrate, wherein the ironing board substrate is configured to flex and compress when receiving vertical pressure. According to another variation, the operable portion of the ironing surface is configured to receive a horizontal input from a user causing the soleplate to tilt so that the front edge moves downward and the rear edge moves upward. According to another variation, the raised pinnacle of the operable portion located along the longitudinal axis is centered along the longitudinal axis.

A second aspect can include a method of making a soleplate for an iron. The method includes forming a front edge and a rear edge of the soleplate, the rear edge located opposite the front edge. The method also includes forming a first side and a second side, the second side located opposite the first side. The method also includes bisecting the front edge and the rear edge, forming a longitudinal axis. The method also includes bisecting the first side and the second side, forming a transverse axis. The method also includes locating an intersection located where the longitudinal axis and the transverse axis cross. The method also includes causing an operable portion of an ironing surface of the soleplate to be substantially curved along the longitudinal axis and substantially curved along the transverse axis, forming a raised pinnacle of the operable portion located along the longitudinal axis at a point other than the intersection, the raised pinnacle forming a highest point on the operable portion. Other variations of the second aspect are contemplated and described, herein.

These and various other features and advantages will be apparent from a reading of the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a top view of a curved soleplate 100, according to various embodiments. Soleplate 100 is intended for use with an iron assembly (iron), such as iron 700 depicted in FIGS. 7A-7B.

FIG. 2 is a front profile view of curved soleplate 100, according to various embodiments.

FIG. 3 shows s a rear profile view of curved soleplate 100, according to various embodiments.

FIG. 4 illustrates a first side profile view of curved soleplate 100, according to various embodiments.

FIG. 5 is a second side profile view of curved soleplate 100, according to various embodiments. The depiction of soleplate 100, as shown, may be similar to a mirror image of the view shown in FIG. 4.

FIG. 6A-6D are perspective and cross-sectional views of curved soleplate 100, according to various embodiments. FIGS. 6A-6D may be drawn to scale with respect to each other, according to various embodiments.

FIGS. 7A-7B illustrate a curved soleplate 710 as employed on an example iron 700, as the iron 700 receives input from a user, according to various embodiments.

FIG. 8 is a top view of a curved soleplate 800 having an operable portion 808, according to various embodiments. Soleplate 800 may have some features and design characteristics similar to soleplate 100, according to various embodiments.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

Disclosed are structures and methods relating to irons and associated iron soleplates that are designed to reduce ironing effort for a user. By producing a smoother, gliding ironing experience for the user for the highly-repetitive motions involved in ironing, ironing may become less tiresome.

An iron (for example, as shown in FIGS. 7A-7B) includes a soleplate 100. An example soleplate 100 is shown from various perspectives in FIGS. 1-6D. In FIG. 1, a soleplate 100 is viewed from above. FIGS. 2 and 3 are front and rear profile views of soleplate 100, respectively. FIGS. 4 and 5 are side profile views of soleplate 100. FIGS. 6A-6D show perspective and cross-sectional views of soleplate 100, discussed in greater detail, below. Soleplate 100 is preferably intended for use with an iron assembly (iron), such as iron 700 depicted in FIGS. 7A-7B.

Soleplate 100 represents the portion of an iron that typically is heated and that directly or indirectly contacts an ironing surface (shown in FIGS. 7A-7B). Soleplate 100, when viewed from the direction of the surface that will contact a fabric to be ironed (as shown in FIG. 1), has an outline with a roughly triangular, lobed shape. According to various embodiments, at least a portion of soleplate 100 is shaped in three dimensions to include a curved surface having curves in at least two directions. The directions of curvature maybe perpendicular to each other and are centered, in this example, at a highest domed point on the soleplate 100, referred to as a pinnacle 115. Pinnacle 115 may be a raised pinnacle 115, according to various embodiments. The soleplate 100 has a curved surface in both a longitudinal direction (along or parallel to axis 124) and in a transverse direction (along or parallel to axis 130) perpendicular to the longitudinal direction that intersect at the pinnacle 115. The location and more precise characteristics of the surface curves of soleplate 100 are described in greater detail, below.

Per FIG. 1, the surface of soleplate 100 that will contact the fabric to be ironed is facing up. The soleplate 100 has a front edge 118 opposite a rear edge 116. Soleplate 100 also has a first side edge 120 and a second side edge 122 on opposing sides of the soleplate 100, which at least partially define an outline of the soleplate 100. In order to define the curvature of soleplate 100, as shown, a longitudinal axis 124 is shown bisecting the front edge 118 and the rear edge 116. The longitudinal axis 124 also defines a symmetrical axis of soleplate 100. Likewise, a transverse axis 130 bisects the first side edge 120 and the second side edge 122 of soleplate 100 based upon the length of the longitudinal axis from 118 to 116. The transverse axis 130 preferably does not form an axis of symmetry, according to the shown embodiment. The longitudinal axis 124 and the transverse axis 130 cross at an intersection 128 near a center of the soleplate 100. The intersection 128 may serve as a geographic location and a point of reference to define surface curvature geometry of the soleplate 100 and as relevant to the location of the pinnacle 115. Contour lines are shown on the curved surface of soleplate 100 in FIG. 1, showing relative curvature and topographies, in addition to contours of any curvature on the soleplate 100 surface. As shown, the contour lines may not be drawn to scale, and various curvatures are contemplated.

Parallel to transverse axis 130 is a transverse pinnacle line 126 that, as shown, is nearer to front edge 118 than is the transverse axis 130. The pinnacle 115 and highest point of soleplate 100 is preferably located at the intersection of longitudinal axis 124 and the transverse pinnacle line 126. The pinnacle 115 is preferably located forward of the intersection 128 for reasons discussed below, but may alternatively be located at another point on the surface of the soleplate 100. According to various embodiments, the pinnacle 115 may preferably be located along longitudinal axis 124. The pinnacle 115, and surface curvature related thereto, may be centered on the transverse pinnacle line 126, as shown, but may be longitudinally at another location on the surface of soleplate 100 other than longitudinal axis 124.

Various degrees of slope and/or curvature may be formed around and sloping down from the pinnacle 115, which is the highest point on soleplate 100, according to the shown embodiment. Contour lines represent varying topographies on soleplate 100 surrounding the pinnacle 115, but are not meant to be limiting and are not intended to be drawn to scale. A center of mass location of the iron or soleplate 100 may be determined based on the weight, curvature, and composition of soleplate 100. The center of mass may also take into account the weight or placement of a hand of a typical user as positioned during ironing, and/or pressure typically applied by a user during ironing. The center of mass may be the intersection 128, the pinnacle 115, or elsewhere, according to various embodiments.

Unlike existing soleplates, the surface of the disclosed soleplate 100 is generally sloped with curves from a pinnacle 115 on the soleplate 100 creating a dome-like shape, which may be asymmetrical. The pinnacle 115 may also represent a highest point, peak, summit, relative maximum, etc. of the soleplate 100. The intersection 128 may also be located at a center of mass or a geometric center of the iron. The pinnacle 115 may be located directly or roughly above, based on the perspective of this view, the center (or mass or geometric) for the entire iron (see FIGS. 7A-7B) or the soleplate 100 alone, according to various embodiments. The intersection 128 may be aligned with the pinnacle 115, according to various embodiments. Pinnacle 115 may also represent a general pinnacle region or plateau if a pinnacle 115 is not precisely or clearly definable.

From the pinnacle 115, the remainder of the soleplate 100 preferably slopes away and tapers at least partially off as the surface approaches the various edges of the soleplate 100, leading to thinner edges (vertically) of described soleplate 100, according to some embodiments. Slope and taper of the surface curvature may include portions of linear and/or preferably rounded curvature, according to various embodiments. The thickness of the soleplate 100 at the various edges may not be uniform, with more thickness located near pinnacle 115. The soleplate 100 may alternatively have a uniform thickness, but retain a curved surface, or may have a varied thickness, as illustrated in FIGS. 6B-6D. Preferably, the surface curvature of soleplate 100 includes slope and taper, as shown in the various views depicted in FIGS. 1-6D. The soleplate 100 may taper away from pinnacle 115 and may have relatively less taper in some areas and relatively more taper in others, with various edges (e.g., 116, 118, 120, 122) equal in height or only slightly lower than the pinnacle 115 of the soleplate 100, according to some embodiments.

FIG. 2 depicts soleplate 100 rotated so as to be viewed from a front profile view, and three general transverse sections have been identified, including a center section 218, a first side section 220, and a second side section 222. Front edge 118 is shown at the front of soleplate 100. As shown, the center section 218 of soleplate 100 includes the pinnacle 115. Soleplate 100, as shown in FIG. 2, has horizontal reflective symmetry from the front profile view. The horizontal reflective symmetry may be symmetric about a vertical axis located near a tip of front edge 118, according to various embodiments. Preferably, first side section 220 and second side section 222 therefore are generally mirror images of each other. First and second side sections 220 and 222 depict a generally downsloping curved taper as they approach the respective side edges of the soleplate 100. Between the side sections 220 and 222, is the center section 218, which is at a highest point at pinnacle 115 that is located on the longitudinal axis 124 of 100, shown in FIG. 1. Center section 218 may appear substantially flat, but preferably contains a gentle curvature along the top of the soleplate 100. Steam holes are visible on a surface in center section 218, but are not of particular relevance the scope of this disclosure.

Per FIG. 3, soleplate 100 is shown in a rear profile view, and three general transverse sections have been identified, similar to the sections shown in FIG. 2. The view in FIG. 3 may be a reversed view of soleplate 100 as compared to the view of FIG. 2, and rear edge 116 is shown at the rear of soleplate 100.

A center section 318 (which may be similar to 218), first side section 320 (which may be similar to 220), and a second side section 322 (which may be similar to 222) are identified. Similar to FIG. 2, a pinnacle 115 is shown at the center (from this view) of the center section 318, located along the longitudinal axis shown in FIG. 1. The remainder of the soleplate 100 generally slopes away from pinnacle 115, at various degrees of slope and curvature. A substantial portion of rear edge 116 is located in the center section 318, and the soleplate 100 generally slopes down in a direction toward the rear edge 116, as shown.

A first of two side profile views of a soleplate 100 having a curved surface, is shown in FIG. 4, according to various embodiments. As shown, soleplate 100 contains three identified longitudinal sections, including a center section 416, a front section 418, and a rear section 420. Front section 418 includes the front edge 118, and rear section 420 includes the rear edge 116. Center section includes a portion of the first side edge 120, which may also span the front section 418 and/or the rear section 420, as shown.

The overall curvature of soleplate 100 is preferably gradual as viewed in the side profile views of FIGS. 4 and 5. A pinnacle 115 is located at or near the longitudinal center of center section 416, as shown. Soleplate 100, as shown, slopes away as a curve from pinnacle 115 downwardly away from pinnacle 115 to the front edge 118 and the rear edge 116. Center section 416 is preferably not centered at a longitudinal midpoint of soleplate 100, but is preferably instead biased further forward, in the direction of front section 418 and/or front edge 118. Front section 418 may thus cover a smaller geographic area than rear section 420 (as shown), or vice-versa, according to various embodiments. Shown is the preferred embodiment of soleplate 100 where pinnacle 115 is at a transverse center (e.g., of mass or geometric) of the soleplate 100. The pinnacle 115 may also be shifted further forward from intersection (e.g., 128 of FIG. 1), in the direction of front section 418, or to a side, according to various embodiments.

FIG. 5 depicts a second side profile view of a soleplate 100 having a curved surface, according to various embodiments. The depiction of soleplate 100, as shown, may be similar to a mirror image of the view shown in FIG. 4 and may depict the three identified longitudinal sections, including a center section 416, a front section 418, and a rear section 420. Front section 418 includes the front edge 118, and rear section 420 includes the rear edge 116. Center section includes a portion of the first side edge 122, which may also span the front section 418 and/or the rear section 420, as shown.

As in FIG. 4, a pinnacle 115 is located at or near the longitudinal center of center section 416. Soleplate 100, as shown, slopes away as a curve from pinnacle 115 to the front edge 118 and the rear edge 116. Center section 416 is preferably not centered at a longitudinal midpoint centered at a midpoint of soleplate 100, but may instead be biased further forward, in the direction of front section 418 and/or front edge 118. Front section 418 may cover a smaller geographic area than rear section 420 (as shown), or vice-versa, according to various embodiments. Shown is the preferred embodiment of soleplate 100 where pinnacle 115 is at a longitudinal center (e.g., of mass or geometric) of the soleplate 100. The pinnacle 115 may also be shifted further forward from intersection (e.g., 128 of FIG. 1), in the direction of front section 418, or to a side, according to various embodiments.

FIG. 6A is an illustrative perspective view of a soleplate 100 from which various cross-sectional views 600, 602, and 604, of FIGS. 6B, 6C, and 6D, respectively, are derived. The pinnacle 115 may be located at a highest point on the surface of soleplate 100. The thickness of soleplate 100 may vary between areas, as illustrated with respect to FIGS. 6B-6D, herein.

A first cross-sectional view 600 of soleplate 100 in FIG. 6B shows a planar cut that highlights a curved and varied thickness of soleplate 100 longitudinally forward of, but not including, pinnacle 115. Therefore a relative peak thickness of soleplate 100 at view 600 is less than a maximum soleplate 100 thickness. The shown cross-sectional view 600 depicts a portion of soleplate 100, which may lie longitudinally forward of pinnacle 115, according to various embodiments. The cross-sectional view 600 of soleplate 100 depicts a relative thickness of soleplate 100 at one particular transverse plane located along longitudinal axis 124 described with reference to FIG. 1.

A second cross-sectional view 602 shows a planar cut that highlights a curved and varied thickness of soleplate 100 longitudinally at or near the thickest point of soleplate 100, and the location of pinnacle 115. The shown cross-sectional view 602 may depict a thickest portion of soleplate 100, which may lie longitudinally near pinnacle 115, according to various embodiments. The cross-sectional view 602 of soleplate 100 depicts a relative thickness of soleplate 100 at a second particular transverse plane located along longitudinal axis 124 described with reference to FIG. 1.

A third cross-sectional view 604 illustrates a planar cut that highlights a curved and varied thickness of soleplate 100 longitudinally rear of the thickest point and pinnacle 115 of soleplate 100. The shown cross-sectional view 604 may depict a relatively thin portion of soleplate 100, which may lie longitudinally rear of pinnacle 115, according to various embodiments. The cross-sectional view 604 of soleplate 100 depicts a relative thickness of soleplate 100 at a third particular transverse plane located along longitudinal axis 124 described with reference to FIG. 1.

Steam holes 110 together can form an arched shape, as viewed in FIG. 1, and can roughly follow the shape of the various edges of soleplate 100, according to the shown embodiment of FIG. 1.

Two front mounting tabs 112 and two rear mounting tabs 114 are shown according to the various views, but more, fewer, or different styles of mounting tabs may be employed on soleplate 100, according to various embodiments. Per FIG. 1, one front mounting tab 112 and one rear mounting tab 114 are shown on each of the first 120 and second 122 side edges of soleplate 100, and may be employed for attachment to an iron housing or other iron components (see FIGS. 7A-7B). Per FIG. 2, front mounting tabs 112 are visible are the sides of the front view soleplate 100. Per FIG. 3, rear mounting tabs 114 are visible at the sides of the rear view of soleplate 100. Per FIGS. 4 and 5, a front mounting tab 112 is located approximately between the front section 418 and the center section 416, and a rear mounting tab 114 is located near the center section 416.

Soleplate 100, may be composed of various substances capable of retaining and transferring heat during ironing, including metal (e.g., aluminum, stainless steel, and the like) and may be polished and/or coated with anti-stick coatings, such as a high grade polytetrafluoroethylene (PTFE). Soleplate 100 may include an internal, embedded electric heating element (not shown), or any other known or developed heating means.

Through polishing and coating a soleplate (such as soleplate 100) ironing friction (static and/or kinetic) may be reduced, but reducing ironing friction even further may be desirable. The soleplate 100, whether composed of metal or other substance, can be formed using conventional metal-forming processes, and may include the use of computer numeric control (CNC), three-dimensional printing, or other fabrication processes known in the art.

FIGS. 7A-7B depict a soleplate 710 having a curved surface, as employed on an example iron 700, as the iron 700 receives movement input from a user, according to various embodiments. Soleplate 710 may be similar to soleplate 100, as described herein.

FIG. 7A depicts an iron 700 at rest on an ironing board 712. As shown, an ironing board 712 may be in contact with iron 700. Ironing board 712 may be a flat, padded, deformable substrate having an internal rigid structure. Ironing board 712 may be composed of a material so as to flex or give when pressure is applied to the ironing board 712 or fabric over the ironing board 712, as well known, which may allow for flexibility and smoother ironing. An iron 700 may interface with an ironing board 712, causing the ironing board 712 to compress or flex where the iron is located and applying pressure to the ironing board 712, compressing the ironing board 712.

Iron 700 includes a housing assembly 714 and a soleplate 710, according to the shown embodiment. Iron 700 with installed soleplate 710 contacts the ironing board 712 through fabric to be ironed (not shown), at least partially deforming the ironing board 712. While at rest, iron 700 (with accompanying soleplate 710) causes an indentation 716 in the ironing board 712 roughly contoured to the outline of the soleplate 710. The indentation 716 may be created having an elongate, dome-shaped recess in the ironing board 712. At various points of the ironing board 712, the iron 700 may apply relatively more pressure, at least partially due to curvature of soleplate 710. Relatively more upward (normal) pressure from the ironing board 712 may be applied on a section of the soleplate 710 that protrudes furthest into the ironing board 712 near indentation 716. For example, the section of soleplate 710 that protrudes further into the ironing board 712 may be similar to pinnacle 115 of FIG. 1-6D.

Soleplate 710 may also utilize the deformability of the ironing board 712 to maintain a relatively uniform heat transfer during ironing. In other words, in the described embodiments, the pinnacle (see 115, FIG. 1) (near indentation 716) and surrounding area of the soleplate 710 may apply a greater pressure and deform or compress an ironing board 712 relatively more, creating the elongate, dome-shaped recess in the ironing board 712. But, due to the compressive nature of the ironing board 712, the various edges of the soleplate 710 may yet largely maintain constant or similar contact with fabric being ironed backed by the ironing board 712.

A resting dihedral angle 720 is defined by the horizontal (longitudinal) plane of the soleplate 710 with respect to the normal. Resting dihedral angle 720 may be roughly a right angle (i.e., 90°).

FIG. 7B depicts iron 700 as it receives input or impulse force from a user (not shown) to move the iron 700 following FIG. 7A.

Using iron 700 equipped with soleplate 710, as disclosed herein, a user may begin by attempting to slide the iron 700 in a particular direction, e.g., forward, (to the left, as shown) along the ironing board 712, with the soleplate 710 in contact with a fabric (not shown). The iron 700, which is configured to receive an ironing input from a user at a point on the iron 700 above the ironing board 712 surface (typically at a handle portion of the housing assembly 714) initially rocks, tilts, or pivots in that direction, generating a torque through the iron 700 from the handle with respect to one or more contact points of the soleplate 710 with the ironing board 712. Upon the receiving the ironing input from the user, the iron 700 may tilt due to the curvature in the soleplate 710.

The tilt may form an active dihedral angle 722 between a plane formed by the soleplate 710, and a vertical plane located at the pinnacle (not shown; may be similar to pinnacle 115), among others. Through the torque of tilting, rotational kinetic energy is transferred to the iron 700 prior to the iron overcoming static friction between the soleplate 710 and the ironing board 712 surface. During tilting of the iron 700, various points on the ironing surface of the soleplate 710 may contact the ironing board 712 surface with varying degrees and surface pressure and some points along the surface of the soleplate 710 may slide (e.g., progressively) against the ironing board 712 surface during the tilting process.

At least some translational momentum may then be generated as the transfer of kinetic energy to the iron 700 gradually transitions from rotational to translational. The momentum generated may overcome static friction between soleplate and fabric and/or ironing board 712 surface, reducing at least the initial input force required from the user to move the iron 700. The resulting effect is the force applied by the user may not require the traditional spike in force required to put the iron 700 in motion, yielding a perceptibly smoother glide and motion onset, and reducing static friction at the onset of iron 700 movement.

According to the shown embodiment, the iron 700 tilts upon receiving an impulse force from the user at a handle, changing resting dihedral angle 720 from a roughly right angle (resting angle) to an acute, active dihedral angle 722. The energy transferred during the tilt, as described herein, may cause various points of contact between the soleplate 710 and the ironing board 712 to break adhesion in a progressive manner, leading to a smoother onset of translational movement of the iron 700 (across the ironing board 712) in a forward (left) direction. During ironing, as depicted, active dihedral angle 722 may momentarily become minimized, and oscillate between roughly resting dihedral angle 720 and active dihedral angle 722, leading to repeated, smooth ironing glide. While tilting upon onset of force, iron 700 (with accompanying soleplate 710) can cause an indentation 718 to form in the ironing board 712 that is roughly contoured to the outline of the soleplate 710. Although the tilt of iron 700 is shown in a longitudinal direction along a longitudinally-curved portion of the soleplate 710, the tilting motion may also function in a transverse direction along a transverse-curved portion of the soleplate 710. The tilting motion may alternatively tilt along any combination of longitudinal and transverse movement (e.g., diagonally), per the various directions of the curved surface of the soleplate 710. Thus, a soleplate of the present disclosure can tilt in any direction from the pinnacle.

During testing, a comparison of static friction between a conventional flat soleplate and a soleplate 710 having a curved surface as described herein was performed. In existing soleplate configurations, initial (static) friction was relatively high, and decreased over time as friction became kinetic. The friction was shown to decrease roughly asymptotically to a steady state friction level. However, with an iron using a soleplate 710 having a curved surface, as described herein, static friction forces is found to be notably lower, and may be roughly 56% lower than a conventional flat iron soleplate, according to various embodiments.

FIG. 8 depicts a top view of a soleplate 800 having a curved surface, having an operable portion 808, according to various embodiments. Soleplate 800 may have some features and design characteristics similar to soleplate 100, according to various embodiments.

Soleplate 800, as illustrated, has an outline with a roughly triangular, lobed shape. Soleplate also has a first side 832 and a second side 834 of the operable portion 808. Soleplate 800 may include an operable portion 808 of an ironing surface. Soleplate has a front edge 838 and a rear edge 836 of the operable portion 808. An operable portion 808 may include the entire ironing surface of the soleplate 800 or a portion thereof, as is shown in FIG. 8. An operable portion 808 of a soleplate 800 ironing surface may be a curved or non-flat portion of a surface of soleplate 800, according to various embodiments. If a portion of the soleplate 800 (e.g., soleplate 100 of FIG. 1, above) ironing surface is operable, another part of the soleplate 800 may be flat, or may lack a curved surface in the region of soleplate 800 outside the operable portion 808. An operable portion 808 of a soleplate 800 may take various forms and may occupy varying amounts of an ironing surface of soleplate 800, and may be positioned differently.

An outline of operable portion 808 may roughly follow an outer shape of soleplate 800 at a fixed distance therefrom, and may define a non-curved, flat surface section between the operable portion 808 at the outline of soleplate 800. Soleplate 800 curvature may be limited to the operable portion 808, according to this embodiment. Operable portion 808 is depicted as partially covering a surface area of soleplate 800, but a larger or smaller operable portion 808 is also contemplated, herein.

Similar to the view of soleplate 100 of FIG. 1, Soleplate 800, when viewed from the side that will contact fabric (as shown), has an outline with a roughly triangular, lobed shape. At least a portion of soleplate 800 is shaped in three dimensions to include a curved surface in at least two directions. The directions or axes of curvature intersect, in this example, at a highest domed point on the soleplate 800, referred to as a pinnacle 815 (which may be similar to pinnacle 115 of FIGS. 1-6D). The operable portion 808 of soleplate 800 has a curved surface in both a longitudinal direction (along axis 824) and in a transverse direction (along axis 830) perpendicular to the longitudinal direction that intersect at the pinnacle 815. The pinnacle 815 may preferably be shifted forward of an intersection 828. The location and more precise characteristics of the surface curves of soleplate 800 are described in greater detail, below.

The surface of soleplate 800 that will contact the fabric is facing up, as shown. The operable portion 808 soleplate surface 800 has a front edge 838 opposite a rear edge 836. The operable portion 808 front 838 and rear 836 edges may be located on soleplate 800 similar to front edge 118 and rear edge 116 of soleplate 100, as depicted in FIG. 1. The first side edge 832 and the second side edge 834 on opposing sides of the operable portion 808 of soleplate 800, which may at least partially define an outline of the soleplate 800 or the operable portion 808 of soleplate 800. In order to define the curvature of soleplate 800 (and the operable portion 808 thereof), as shown, a longitudinal axis 824 is shown bisecting the front edge 838 and the rear edge 836. The longitudinal axis 824 also defines a symmetrical axis of soleplate 800.

Likewise, a transverse axis 830 is shown bisecting the first side edge 832 and the second side edge 834 of the operable portion 808 of soleplate 800, based on a midpoint of longitudinal axis 824. The transverse axis 830 preferably does not form an axis of symmetry, according to the shown embodiment. The longitudinal axis 824 and the transverse axis 830 cross at the intersection 828 near the center of the soleplate 800. The intersection 828 may serve as a geographic location used as a point of reference to define curvature geometry of the soleplate 800 or operable portion 808. Contour lines are shown on the operable portion 808 curved surface of soleplate 800, depicting relative curvature and topographies, in addition to contours of any curvature on the soleplate 800 surface. As shown, the contour lines may not be drawn to scale, and various curvatures are contemplated.

Parallel to transverse axis 830 is a transverse pinnacle line 826 that, as shown, is nearer to front edge 838 than transverse axis 830. The pinnacle 815 and highest point of soleplate 800 is preferably located at the intersection of longitudinal axis 824 and the transverse pinnacle line 826. The pinnacle 815 is preferably located forward of the intersection 828 for reasons discussed below, but may alternatively be located at another point on the surface of the soleplate 800 or operable portion 808. According to various embodiments, the pinnacle 815 may preferably be located along longitudinal axis 824. The pinnacle 815, and surface curvature related thereto, may be centered on the transverse pinnacle line 826, as shown, but may be longitudinally at another location on the operable portion 808 of soleplate 800 other than longitudinal axis 824.

Various degrees of slope and/or curvature may be formed around and sloping down from the pinnacle 815, which is the highest point on soleplate 800, according to the shown embodiment. Contour lines represent varying topographies on soleplate 800 surrounding the pinnacle 815, but are not meant to be limiting and are not intended to be drawn to scale. A center of mass location of the iron or soleplate 800 may be determined based on the weight, curvature, and composition of soleplate 800. The center of mass may also take into account the weight or placement of a hand of a typical user as positioned during ironing, and/or pressure typically applied by a user during ironing. The center of mass may be the intersection 828, the pinnacle 815, or elsewhere, according to various embodiments.

Similar to soleplate 100, but unlike existing soleplates, the surface of disclosed soleplate 800 is generally sloped with curves from a pinnacle 815 on the soleplate 800 creating a dome-like shape, which may be asymmetrical. The pinnacle 815 may also represent a highest point, peak, summit, relative maximum, etc. of the soleplate 800. The intersection 828 may also be located at a center of mass or a geometric center of the iron. The pinnacle 815 may be located directly or roughly above, based on the perspective of this view, a center (e.g., of mass or geometric) for the entire iron (see FIGS. 7A-7B) or the soleplate 800 alone, according to various embodiments. The intersection 828 may be aligned with the pinnacle 815, according to various embodiments. Pinnacle 815 may also represent a general pinnacle region or plateau if a pinnacle 815 is not precisely definable.

From the pinnacle 815 in the soleplate 800, the remainder of the operable portion 808 of soleplate 800 preferably slopes away and tapers at least partially off as the surface approaches the various edges of the operable portion 808. Slope and taper of the surface curvature may include portions of linear and/or preferably rounded curvature, according to various embodiments. The thickness of the soleplate 800 at the various edges may not be uniform, with more thickness located near pinnacle 815. The soleplate 800 may alternatively have a uniform thickness, but retain a curved surface, or may have a varied thickness. Preferably, the surface curvature of operable portion 808 includes slope and taper. The operable portion 808 of soleplate 800 may taper away from pinnacle 815 and may have relatively less taper in some areas and relatively more taper in others, with various edges (e.g., 832, 834, 836, 838) equal in height or only slightly lower than the pinnacle 815 of the soleplate 800, according to some embodiments.

Two front mounting tabs 812 and two rear mounting tabs 814 are depicted, but more or fewer, or different styles of mounting tabs may be employed on soleplate 800, according to various embodiments. Steam holes 810 together form an arched shape, and roughly follow the contours of the various edges of soleplate 800, according to the shown embodiment.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. 

What is claimed is:
 1. A soleplate for use with an iron, comprising: an operable portion of an ironing surface having a front edge located opposite a rear edge, and having a first side located opposite a second side; a longitudinal axis bisecting the front edge and the rear edge; a transverse axis bisecting the first side and the second side based on a midpoint of the longitudinal axis; and an intersection located where the longitudinal axis and the transverse axis cross; wherein the operable portion of the ironing surface is substantially curved along the longitudinal axis and substantially curved along the transverse axis, forming a raised pinnacle of the operable portion located along the longitudinal axis at a point other than the intersection, the raised pinnacle forming a highest point on the operable portion.
 2. The soleplate of claim 1, wherein the operable portion of the ironing surface is substantially longer along the longitudinal axis than the transverse axis.
 3. The soleplate of claim 1, wherein the operable portion of the ironing surface is curved to reduce static friction during ironing.
 4. The soleplate of claim 1, wherein the substantially curved operable portion of the ironing surface along the longitudinal axis is parabolically curved such that the intersection is higher than the average of the front edge and rear edge.
 5. The soleplate of claim 1, wherein the substantially curved ironing surface along the transverse axis is parabolically curved such that the intersection is higher than the average of the first side and the second side.
 6. The soleplate of claim 1, wherein the operable portion of the ironing surface is configured to interface with an ironing board substrate, wherein the ironing board substrate is configured to flex and compress when receiving vertical pressure.
 7. The soleplate of claim 1, wherein the operable portion of the ironing surface is configured to receive a horizontal input from a user causing the soleplate to tilt so that the front edge moves downward and the rear edge moves upward.
 8. The soleplate of claim 1, wherein the raised pinnacle of the operable portion located along the longitudinal axis is centered along the longitudinal axis.
 9. An ironing device, comprising: a handle configured to receive ironing input from a user; a heating element configured to heat a soleplate proximate to the heating element and rigidly connected to the handle; and wherein the soleplate is configured to include: an operable portion of an ironing surface having a front edge located opposite a rear edge, and having a first side located opposite a second side; a longitudinal axis bisecting the front edge and the rear edge; a transverse axis bisecting the first side and the second side based on a midpoint of the longitudinal axis; and an intersection located where the longitudinal axis and the transverse axis cross; wherein the operable portion of the ironing surface is substantially curved along the longitudinal axis and substantially curved along the transverse axis, forming a raised pinnacle of the operable portion located along the longitudinal axis at a point other than the intersection, the raised pinnacle forming a highest point on the operable portion.
 10. The ironing device of claim 9, wherein the operable portion of the ironing surface is substantially longer along the longitudinal axis than the transverse axis.
 11. The ironing device of claim 9, wherein the substantially curved operable portion of the ironing surface along the longitudinal axis is parabolically curved such that the intersection is higher than the average of the front edge and rear edge.
 12. The ironing device of claim 9, wherein the substantially curved ironing surface along the transverse axis is parabolically curved such that the intersection is higher than the average of the first side and the second side.
 13. The ironing device of claim 9, wherein the operable portion of the ironing surface is configured to receive a horizontal input from a user causing the soleplate to tilt so that the front edge moves downward and the rear edge moves upward.
 14. The ironing device of claim 9, wherein the raised pinnacle of the operable portion located along the longitudinal axis is centered along the longitudinal axis.
 15. A method of making a soleplate for an iron, comprising: forming a front edge and a rear edge of the soleplate, the rear edge located opposite the front edge; forming a first side and a second side, the second side located opposite the first side; bisecting the front edge and the rear edge, forming a longitudinal axis; bisecting the first side and the second side, forming a transverse axis; locating an intersection located where the longitudinal axis and the transverse axis cross; and causing an operable portion of an ironing surface of the soleplate to be substantially curved along the longitudinal axis and substantially curved along the transverse axis, forming a raised pinnacle of the operable portion located along the longitudinal axis at a point other than the intersection, the raised pinnacle forming a highest point on the operable portion.
 16. The method of claim 15, wherein the operable portion of the ironing surface is caused to be substantially longer along the longitudinal axis than the transverse axis.
 17. The method of claim 15, wherein the substantially curved operable portion of the ironing surface along the longitudinal axis is caused to be parabolically curved such that the intersection is higher than the average of the front edge and rear edge.
 18. The method of claim 15, wherein the substantially curved ironing surface along the transverse axis is caused to be parabolically curved such that the intersection is higher than the average of the first side and the second side.
 19. The method of claim 15, wherein the operable portion of the ironing surface is configured to receive a horizontal input from a user causing the soleplate to tilt so that the front edge moves downward and the rear edge moves upward.
 20. The method of claim 15, wherein the raised pinnacle of the operable portion located along the longitudinal axis is caused to be centered along the longitudinal axis. 